Sad this site is indulging in quackery. Oh well.
Quote from: aceshigh on 04/29/2015 04:46 pmQuote from: cfs on 04/29/2015 03:58 pmQuote from: Rodal on 04/29/2015 02:46 pmQuote from: JasonAW3 on 04/29/2015 02:29 pm....This may seem dumb, but why not set up a Kickstarter for this? ..See this great post: http://forum.nasaspaceflight.com/index.php?topic=36313.msg1364627#msg1364627by the present President (as well as a Trustee) of the renowned Space Studies Institute (www.ssi.org) which was originally founded by G.K. O'NeillSo if I'm reading this correctly, what we need to do is set up a Kickstarter to donate money to ISS's exotic propulsion funds, which can then in turn be given to Eagleworks I am not sure, but I guess that they would not be able to accept donations/kickstarters to a particular project. I guess they can accept money but the distribution of the total sum is decided by them?which would maybe somehow prevent the exact thing that makes NASA not accept donations/kickstarters.Quote from: HMXHMX http://forum.nasaspaceflight.com/index.php?topic=36313.msg1364627#msg1364627we established a fund to support "Exotic Propulsion" which is named (appropriately but uninspiringly*) the "Exotic Propulsion Initiative. It is possible to donate to the fund at our website. SSI is a 501(c)3 non-profit and thus contributions are tax-deductiable. Targeted contributions go almost 100% to the named projects since we have very modest overhead costs (we don't pay salaries to our volunteer staff, for example).unless HMXHMX cares to post further answers, it is advisable that anybody having further questions on SSI donations directly addresses them to the Contact listed at www.ssi.org Space Studies Institute16922 Airport Blvd.#24Mojave, CA 93501PHONE (661) 750-2774EMAIL [email protected]and further inquires about destination of funds for targeted tax-deductible contributions, particularly if they have an interest in targeting a specific effort with their funds.
Quote from: cfs on 04/29/2015 03:58 pmQuote from: Rodal on 04/29/2015 02:46 pmQuote from: JasonAW3 on 04/29/2015 02:29 pm....This may seem dumb, but why not set up a Kickstarter for this? ..See this great post: http://forum.nasaspaceflight.com/index.php?topic=36313.msg1364627#msg1364627by the present President (as well as a Trustee) of the renowned Space Studies Institute (www.ssi.org) which was originally founded by G.K. O'NeillSo if I'm reading this correctly, what we need to do is set up a Kickstarter to donate money to ISS's exotic propulsion funds, which can then in turn be given to Eagleworks I am not sure, but I guess that they would not be able to accept donations/kickstarters to a particular project. I guess they can accept money but the distribution of the total sum is decided by them?which would maybe somehow prevent the exact thing that makes NASA not accept donations/kickstarters.
Quote from: Rodal on 04/29/2015 02:46 pmQuote from: JasonAW3 on 04/29/2015 02:29 pm....This may seem dumb, but why not set up a Kickstarter for this? ..See this great post: http://forum.nasaspaceflight.com/index.php?topic=36313.msg1364627#msg1364627by the present President (as well as a Trustee) of the renowned Space Studies Institute (www.ssi.org) which was originally founded by G.K. O'NeillSo if I'm reading this correctly, what we need to do is set up a Kickstarter to donate money to ISS's exotic propulsion funds, which can then in turn be given to Eagleworks
Quote from: JasonAW3 on 04/29/2015 02:29 pm....This may seem dumb, but why not set up a Kickstarter for this? ..See this great post: http://forum.nasaspaceflight.com/index.php?topic=36313.msg1364627#msg1364627by the present President (as well as a Trustee) of the renowned Space Studies Institute (www.ssi.org) which was originally founded by G.K. O'Neill
....This may seem dumb, but why not set up a Kickstarter for this? ..
we established a fund to support "Exotic Propulsion" which is named (appropriately but uninspiringly*) the "Exotic Propulsion Initiative. It is possible to donate to the fund at our website. SSI is a 501(c)3 non-profit and thus contributions are tax-deductiable. Targeted contributions go almost 100% to the named projects since we have very modest overhead costs (we don't pay salaries to our volunteer staff, for example).
Quote from: LasJayhawk on 04/29/2015 09:55 pmI am somewhat curious as to why AM modulation would increase the drives output. Is it possible that the modulation scheme is increasing the average power output, or is something else in play.I'm wondering what it would do with pulsed RF at a high rep rate?That amplitude, frequency and phase modulation of the carrier wave results in greater thrust force is a prediction from Dr. White's computer code, and not yet an experimentally proven fact. What we know in this regard is that the experimenters in the UK and China claim to have measured greater thrust force using a magnetron (for whatever reason) and that a magnetron performs amplitude, frequency and phase modulation of the carrier wave. We should exercise caution as neither the UK, nor the Chinese teams have been as forthcoming with data as NASA Eagleworks. Those experiments (using a magnetron) remain to be replicated at NASA Eagleworks.Concerning what a pulsed RF at a high rep rate would do, I expect that is something that Dr. White should be able to input in his code and give you an answer, but again whether such an answer from his computer code would be correct remains to be confirmed.My understanding is that NASA Eagleworks is planning to replicate this June the experiments in the UK and China using a magnetron.
I am somewhat curious as to why AM modulation would increase the drives output. Is it possible that the modulation scheme is increasing the average power output, or is something else in play.I'm wondering what it would do with pulsed RF at a high rep rate?
So other than what is described in the links below, is there any proof that plane waves can travel slower or faster than c in vacuum?http://www.sciencemag.org/content/347/6224/857http://arxiv.org/abs/1411.3987
http://en.m.wikipedia.org/wiki/Scharnhorst_effectStill very much not proven.
I've been following this since New Scientist got in hot water for publishing an article on Shawyer's work back in 2006. It's exciting to see it has not been yet falsified. The debate and contributions in this thread remind me of the SpaceX video fixing effort; NSF is transcending the traditional role of forums and becoming some kind of collaborative knowledge creation nexus. Preamble over, I have a suggestion (and hopefully this makes it clear why this comment is here rather than in the article thread): There are lots of new posters who are bringing up problems which have already been addressed up thread. One of the problems of the linear thread style discussion is that it makes it difficult for people to see what has been done. The new article is a wonderful overview of the work, but I wonder if there's room for a page/article/site which lists possible sources of error/standard criticisms of the physical impossibility (maybe each as a linkable heading), and describes clearly what has been done to eliminate them from the system or accurately measure errors, and to theoretically address apparent contradictions to physical laws. I have in mind something like Grist's 'how to talk to a climate sceptic' (http://grist.org/series/skeptics/) where many common talking point issues with AGW are listed, and debunked.It could be useful if this list were editable like a wiki, so that when someone comes with a complaint already addressed, they can be directed to read that page in general, or linked to the explanation of their issue in particular, but also, if the suggestion is new, it can be easily added as an 'as yet un-eliminated issue' and can await further data.
can anyone explain this point better?from http://emdrive.com/faq.htmlQ. Why does the thrust decrease as the spacecraft velocity along the thrust vector increases?A. As the spacecraft accelerates along the thrust vector, energy is lost by the engine and gained as additional kinetic energy by the spacecraft. This energy can be defined as the thrust multiplied by the distance through which the thrust acts. For a given acceleration period, the higher the mean velocity, the longer the distance travelled, hence the higher the energy lost by the engine.This loss of stored energy from the resonant cavity leads to a reduction in Q and hence a reduction of thrust.The key question is why can't you just turn the machine off and start again from a new reference frame, giving you a traditional interpretation of a propellentless drive and free energy.
Quote from: KelvinZero on 04/30/2015 09:22 amcan anyone explain this point better?from http://emdrive.com/faq.htmlQ. Why does the thrust decrease as the spacecraft velocity along the thrust vector increases?A. As the spacecraft accelerates along the thrust vector, energy is lost by the engine and gained as additional kinetic energy by the spacecraft. This energy can be defined as the thrust multiplied by the distance through which the thrust acts. For a given acceleration period, the higher the mean velocity, the longer the distance travelled, hence the higher the energy lost by the engine.This loss of stored energy from the resonant cavity leads to a reduction in Q and hence a reduction of thrust.The key question is why can't you just turn the machine off and start again from a new reference frame, giving you a traditional interpretation of a propellentless drive and free energy.Reading that Q/A, ascribing a 'book-keeping' ability to such a device in regards to reference frames sounds unphysical to me. I can't do anything with that. I tend to believe that Mr. Shawyer might have accidentally found something mind-blowing.. but his explanations just don't add up. It might work for, uh, different reasons than he assumes.
Contra the usual popularisations, Special Relativity doesn't remove the possibility of a preferred reference frame for the Universe, it just makes it very hard to observe. An alternative, being explored, is Lorentzian relativity, which experimentally gives much the same results as SR, but an absolute frame is preserved. This makes 'accounting' for one object's energy relative to another quite straightforward. These thrusters might provide one means of experimentally determining which version of Relativity is correct.
I'm aware that my technical skills are most likely inferior to most of the ppl working at Eagleworks, so I've been pondering if it would be wise to bring up the following issue, but ah, why not...About the high powered Shawyer-like rotating demonstrator that Eagleworks is building to be ready by june:One of the main criticism about the non-vacuum demonstrator that Shawyer build, to showoff one of his early EMdrive workings, was that - according to critics - some kind of hot air jet was leaking from non-welded micro openings at the large base of the frustum.I understand that Eagleworks will also not operate their version in vacuum, as its purpose is to illustrate an effective motion generated by the EM drive. Consequently they will most likely encounter the same remarks...Countering that "hot air jet" criticism is fairly easy : just build an open enclosure that, in case of a leakage jet , would generate an opposing reaction force to the direction the frustum is supposed to go.IF the setup turns clockwise, then some sort of hot jet is indeed in play, however...if it rotates counterclockwise then clearly, the EMdrive is for real...In all honesty, a simple well taped cardboard enclosure would be enough, just to redirect the supposedly reactionary "exhaust" forces... Of course , testing with and without enclosure is a must, for reference.This upcoming test in June will be a real "make or brake" event. No more endless discussions about measurement procedures and potential measurement errors. I'm sooo in anticipation modus now.. All it needs to do is...TURN in the right direction.
Quote from: Rodal on 04/29/2015 10:19 pmQuote from: LasJayhawk on 04/29/2015 09:55 pmI am somewhat curious as to why AM modulation would increase the drives output. Is it possible that the modulation scheme is increasing the average power output, or is something else in play.I'm wondering what it would do with pulsed RF at a high rep rate?That amplitude, frequency and phase modulation of the carrier wave results in greater thrust force is a prediction from Dr. White's computer code, and not yet an experimentally proven fact. What we know in this regard is that the experimenters in the UK and China claim to have measured greater thrust force using a magnetron (for whatever reason) and that a magnetron performs amplitude, frequency and phase modulation of the carrier wave. We should exercise caution as neither the UK, nor the Chinese teams have been as forthcoming with data as NASA Eagleworks. Those experiments (using a magnetron) remain to be replicated at NASA Eagleworks.Concerning what a pulsed RF at a high rep rate would do, I expect that is something that Dr. White should be able to input in his code and give you an answer, but again whether such an answer from his computer code would be correct remains to be confirmed.My understanding is that NASA Eagleworks is planning to replicate this June the experiments in the UK and China using a magnetron.Dr. Rodal:"That amplitude, frequency and phase modulation of the carrier wave results in greater thrust force is a prediction from Dr. White's computer code, and not yet an experimentally proven fact."I think I may have verified today the need for large time rate of change of the resonant circuit phase changes as the RF amplifier driven 1,937.088 MHz, +/- ~25kHz sine wave oscillates back and forth through the resonance frequency of the frustum cavity. Through a methodical tuning campaign using our triple stub Z-matching tuner and 2 feet of RG-8 coax as the main transmission line to the frustum, I marched the Smith Chart solution circle around its impedance space while checking the thrust output for each over a dozen stub tuner configurations. Only those tuning solutions that maximized the phase change through resonance over the smallest frequency span generated the largest thrust signatures and in fact it overcame its lower Q-factors that those solutions provided. In fact a running solution that yielded Q-factor solutions as high as 7,500 were out performed by two or even three to one in thrust output by tuning solutions that had half these peak Q-factors, but maximized the resonant phase change per kHz. And yes, the input power was maintained at around 50W for all tests. More data later this week as I continue this investigation.BTW, our Eagleworks Dynamics of the Quantum Vacuum paper has finally been published on the NASA/NTRS server. You can find it here: http://tinyurl.com/mw64rsnBest, Paul M.
Quote from: Star-Drive on 02/15/2015 04:17 amFolks:In the meantime, lets ask why 60 watts of relatively harmonic free sine-wave RF power at the 1,937.118 MHz AKA the TM212 resonant frequency in this copper frustum cavity, can only generate a paltry ~60uN, whereas the Chinese claimed to have produce 160,000uN using just ~150 watts of 2,450 MHz RF signals from a magnetron? The magnetron RF signal source that is anything but a pure sine-wave generator, that instead has a modulated FM bandwidth of at least +/-30 MHz that is also concurrently amplitude modulated (AM) with thermal electron noise. Taking a critical look at this question, and knowing that the spectral shape of a magnetron looks like (see below) compared to a CW spike. It seems evident that a CW spike isn't the best waveform to use if you want to maximize thrust. Dollars to donuts says the Chinese are making full use of the available bandwidth of their resonant cavity by using that noisy magnetron. Magnetrons have lots of phase noise too. You can't easily use them on phased array radars because of that for example. Now to put this idea to test, Q: What is the bandwidth of the resonant cavity and what is the 90 percent power bandwidth of the signal you are driving it with? What kind of sig gen are you using? Can it do FM? Can you do any advanced waveforms like a PSK waveform? Do you have a way to produce wideband noise or a spread spectrum carrier for your testing? Can you do any waveforms like at the bottom?Also during researching other possible theories which could explain Emdrive we found ample literature stating that molecules acquire a kinetic momentum during the switching of the magnetic field as a result of its interaction with the vacuum field. If correct, that may well be a very significant lead. So that raises the question, how does one increase the switching rate? What about phase shifting? http://en.wikipedia.org/wiki/Phase-shift_keyingPhase shifting seems important. https://www.viasat.com/files/assets/web/datasheets/EBEM_MD-1366_043_web.pdfOne of these driving your amp would be helpful. They go up to 2ghz.
Folks:In the meantime, lets ask why 60 watts of relatively harmonic free sine-wave RF power at the 1,937.118 MHz AKA the TM212 resonant frequency in this copper frustum cavity, can only generate a paltry ~60uN, whereas the Chinese claimed to have produce 160,000uN using just ~150 watts of 2,450 MHz RF signals from a magnetron? The magnetron RF signal source that is anything but a pure sine-wave generator, that instead has a modulated FM bandwidth of at least +/-30 MHz that is also concurrently amplitude modulated (AM) with thermal electron noise.
Quote from: Mulletron on 04/30/2015 05:22 amhttp://en.m.wikipedia.org/wiki/Scharnhorst_effectStill very much not proven.I don't think this proves it but it looks experimental.http://cds.cern.ch/record/370620 from (https://scholar.google.com/scholar?cluster=1710259071594791986&hl=en&as_sdt=0,48)Making the vacuum devoid of energy, (wavelengths restricted from existing between the 2 plates) I would assume might change the vacuum dielectric constant to lower than one. Having an abundance of energy, giving a dielectric greater than one. Maybe similar to how light might slow down near large gravitational objects, though when measured inside the field it still appears, because of shrunken rulers, that light velocity is still the same. Another paper starting on page 14 that suggest super-luminal tunneling (http://arxiv.org/pdf/1008.1640v2.pdf).This one seems to deal with it specifically (http://arxiv.org/abs/0901.0508). one dealing with single photons (http://arxiv.org/abs/0708.3889)appears connected (http://www.emis.ams.org/journals/SIGMA/2014/005/sigma14-005.pdf) (discusses moving faster than light)Thanks for pointing out where the idea came from for the super luminal propagation between plates. Hmm, I suppose from the link you gave it suggests the effect is not measurable (change in velocity) which contrasts with the experimental claim of having measured super-luminal velocity. Interesting.
Quote from: Dmytry on 04/29/2015 04:18 amWell, one shouldn't even see a drift the size of the measured force, when it's not even sub-micronewton range.If one is heating metal, one is probably heating it unevenly, and it bends as long as heat is applied (the hotter material expands more), with a fairly short time constant (because the temperatures will equalize quickly once the heat source is off). Then the heat gets slowly conducted to another structural element, and that structural element happens to bend in a way that influences the experiment in the other direction. How much each structural element will bend will depend to how tight the screws are tightened, what stresses are already in the metal, and so on and so forth; it's essentially impossible to account for.Heat transfer, thermal expansion, thermal stress analysis for uncoupled and for coupled problems, in static and dynamic problems of complicated geometry and materials can be analyzed and modeled with Finite Element analysis (NASTRAN, ANSYS, ABAQUS, ADINA, COMSOL, etc.), just like rockets, spacecrafts and military and commercial aircraft have been analyzed for decades.
Well, one shouldn't even see a drift the size of the measured force, when it's not even sub-micronewton range.If one is heating metal, one is probably heating it unevenly, and it bends as long as heat is applied (the hotter material expands more), with a fairly short time constant (because the temperatures will equalize quickly once the heat source is off). Then the heat gets slowly conducted to another structural element, and that structural element happens to bend in a way that influences the experiment in the other direction. How much each structural element will bend will depend to how tight the screws are tightened, what stresses are already in the metal, and so on and so forth; it's essentially impossible to account for.
Here is an exact solution of the thermal buckling problem for the EM Drive's truncated cone base:https://www.researchgate.net/publication/268804028_NASA%27S_MICROWAVE_PROPELLANT-LESS_THRUSTER_ANOMALOUS_RESULTS_CONSIDERATION_OF_A_THERMO-MECHANICAL_EFFECTThe issue for analyzing thermal structural effects (and other effects) for the EM Drive project at NASA Eagleworks is not a matter of present ability to be analyzed but is, instead, a matter of scarcity of project resources (money, time, and personnel) to analyze them. For example, NASA's EM Drive truncated cone was made by Paul March himself in Paul March's wife dining room. NO TAXPAYER's tax $$$ involved in its construction.
http://forum.nasaspaceflight.com/index.php?topic=36313.msg1327937#msg1327937Engineers and scientists interested in this project, (like @frobnicat, @notsosureofit, @aero, myself, etc.) have contributed their time as well to model different aspects of this experiment to try to distinguish any artifacts from real effects. Earlier on I contributed results of a fully-coupled nonlinear analysis of the torque pendulum used in the experiment, as well as Autocorrelation, and Power Spectral Density analysis of the data.Concerning the issue of shielding, @aero has contributed a MEEP analysis of evanescent waves leaking from the EM Drive, and possibly interacting with the stainless steeel vacuum chamber. Subsequently, Paul March conducted an experiment with the EM Drive outside the stainless steel chamber that may have nullified that explanation.@Mulletron has contributed his own resources and time to run his own EM Drive experiment from a hanging torsional pendulum.Paul March has contributed detailed information about the experimental set-up, and if you are interested, you can also contribute any engineering, preferably quantitative, theoretical, numerical or experimental analysis you may be able to contribute.